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1.
J Fish Dis ; 40(10): 1405-1415, 2017 Oct.
Article in English | MEDLINE | ID: mdl-28422305

ABSTRACT

Updated morphological and histopathological descriptions for Dicauda atherinoidi (Bivalvulida:Myxobolidae) and an expanded host range are supplemented with the first molecular data and phylogenetic analyses of the genus. Plasmodia were located on the head, ventrum/body and fins of infected emerald shiner Notropis atherinoides Rafinesque, 1818 and mimic shiner Notropis vollucellus Cope, 1865, a new host species. Myxospores were spherical, ranging 9.3-11.4 µm (10.5 ± 0.4) in length, 9.0-11.0 µm (9.7 ± 0.4) in width and 6.6-7.0 µm (6.8 ± 0.2) thick in sutural view, and possessed 2-3 caudal processes (5.3-68.3 µm, 31.1 ± 13.6) connected to the spore body at the sutural groove, all of which are consistent with the genus Dicauda. In the absence of available Dicauda sequence data, the 18S rDNA sequences from Michigan isolates were most similar to Myxobolus spp. Phylogenetic analyses clustered these isolates with myxobolid species from cyprinid fish, suggesting these parasites may represent an underpopulated group of cyprinid-infecting myxozoans. Histopathology revealed thin-walled plasmodial pseudocysts in the dermis and associated connective tissue, where granulomatous inflammation and focal scale atrophy were also present. Further sampling/sequencing of myxobolids from Notropis spp. should expand these underrepresented myxozoans and offer further insight into Myxobolidae host family tropisms.


Subject(s)
Cyprinidae , Fish Diseases/epidemiology , Myxozoa/physiology , Parasitic Diseases, Animal/epidemiology , Animals , Fish Diseases/parasitology , Host-Parasite Interactions , Michigan/epidemiology , Myxozoa/classification , Myxozoa/genetics , Parasitic Diseases, Animal/parasitology , Prevalence , RNA, Ribosomal, 18S/genetics
2.
Dis Aquat Organ ; 85(1): 15-22, 2009 May 27.
Article in English | MEDLINE | ID: mdl-19593929

ABSTRACT

This is the first report of natural white spot syndrome virus (WSSV) infection in wild and large-scale farmed crawfish. In the spring of 2007, 3 crawfish farms experienced heavy mortality in ponds populated by Procambarus clarkii and P. zonangulus. Histological examination revealed findings consistent with severe viral infection characterized by numerous intranuclear inclusions in ectodermal and mesodermal tissues. Samples tested by in situ hybridization, injection bioassay in Litopenaeus vannamei, and PCR (nested and real time) were all positive for WSSV. Samples were sent to the National Veterinary Services Laboratory in Ames, Iowa, USA, where WSSV was verified. Subsequently, a multi-parish survey of 184 sites in Louisiana (including farm and wild basin samples) using real-time PCR determined that >60% of sites sampled were positive for WSSV, including wild basin samples.


Subject(s)
Astacoidea/virology , White spot syndrome virus 1/physiology , Animals , Animals, Domestic , Animals, Wild , Epithelium/pathology , Louisiana , Polymerase Chain Reaction
3.
J Clin Invest ; 82(1): 189-97, 1988 Jul.
Article in English | MEDLINE | ID: mdl-2839545

ABSTRACT

Human heart failure is associated with a diminished contractile response to beta-adrenergic agonists. We hypothesized that alterations in the activity of a guanine nucleotide-binding regulatory protein (G protein) might be partially responsible for this abnormality. We therefore measured the activity of G proteins in failing human myocardium utilizing bacterial toxin-catalyzed ADP ribosylation. The activity of a 40,000-mol wt pertussis toxin substrate (alpha G40) was increased by 36% in failing human hearts when compared with nonfailing controls. In contrast, there was no change in the level of the stimulatory regulatory subunit (Gs). The increased activity in alpha G40 was associated with a 30% decrease in basal as well as 5'-guanylyl imidodiphosphate-stimulated adenylate cyclase activity. These data suggest that increased alpha G40 activity is a new marker for failing myocardium and may account at least in part for the diminished responsiveness to beta 1-adrenergic agonists in the failing human heart.


Subject(s)
Adenylate Cyclase Toxin , Cardiomyopathy, Dilated/metabolism , Myocardium/metabolism , Nerve Tissue Proteins/biosynthesis , Pertussis Toxin , Virulence Factors, Bordetella/pharmacology , Adenosine Diphosphate Ribose/metabolism , Adenylyl Cyclases/metabolism , Adolescent , Adult , Cardiomyopathy, Dilated/enzymology , Catalysis , Child , Cholera Toxin/pharmacology , Creatine Kinase/metabolism , Female , Humans , Male , Middle Aged , Molecular Weight , Myocardium/enzymology , Nerve Tissue Proteins/metabolism , Phosphorus Radioisotopes , Receptors, Adrenergic, beta/analysis , Substrate Specificity
4.
Med Hypotheses ; 89: 107-14, 2016 Apr.
Article in English | MEDLINE | ID: mdl-26968922

ABSTRACT

Since 1985, at least nine studies of the average rate of cone loss in retinitis pigmentosa (RP) populations have yielded conflicting average rate constant values (-k), differing by 90-160%. This is surprising, since, except for the first two investigations, the Harvard or Johns Hopkins' protocols used in these studies were identical with respect to: use of the same exponential decline model, calculation of average -k from individual patient k values, monitoring patients over similarly large time frames, and excluding data exhibiting floor and ceiling effects. A detailed analysis of Harvard's and Hopkins' protocols and data revealed two subtle differences: (i) Hopkins' use of half-life t0.5 (or t(1/e)) for expressing patient cone-loss rates rather than k as used by Harvard; (ii) Harvard obtaining substantially more +k from improving fields due to dormant-cone recovery effects and "small -k" values than Hopkins' ("small -k" is defined as less than -0.040 year(-1)), e.g., 16% +k, 31% small -k, vs. Hopkins' 3% and 6% respectively. Since t0.5=0.693/k, it follows that when k=0, or is very small, t0.5 (or t(1/e)) is respectively infinity or a very large number. This unfortunate mathematical property (which also prevents t0.5 (t(1/e)) histogram construction corresponding to -k to +k) caused Hopkins' to delete all "small -k" and all +k due to "strong leverage". Naturally this contributed to Hopkins' larger average -k. Difference (ii) led us to re-evaluate the Harvard/Hopkins' exponential unchanging -k model. In its place we propose a model of increasing biochemical stresses from dying rods on cones during RP progression: increasing oxidative stresses and trophic factor deficiencies (e.g., RdCVF), and RPE malfunction. Our kinetic analysis showed rod loss to follow exponential kinetics with unchanging -k due to constant genetic stresses, thereby providing a theoretical basis for Clarke et al.'s empirical observation of such kinetics with eleven animal models of RP. In contrast to this, we show that cone loss occurs in patients with increasing -k values during RP progression. And as the Hopkins' protocol selects more advanced RP cases than Harvard's to assure avoidance of ceiling effects (Harvard does this by kinetic monitoring), we show increasing -k kinetics to be the reason Harvard obtains more +k and small -k values. Thus the combined effects of (i) and (ii) produce Harvard's smaller average -k value. The relevance of the increasing biochemical stress model for optimizing clinical trials is discussed.


Subject(s)
Apoptosis/physiology , Models, Neurological , Retinal Cone Photoreceptor Cells/pathology , Retinal Cone Photoreceptor Cells/physiology , Retinitis Pigmentosa/pathology , Retinitis Pigmentosa/physiopathology , Cell Survival , Humans , Kinetics
5.
J Am Coll Cardiol ; 9(4): 802-10, 1987 Apr.
Article in English | MEDLINE | ID: mdl-3549838

ABSTRACT

To identify specific histologic abnormalities that could predict early cardiac rejection before the development of myocyte necrosis, 167 consecutive endomyocardial biopsy samples from 18 cardiac transplant recipients were retrospectively analyzed and 17 histologic variables were semiquantitatively graded from 0 to 3. Forty-five biopsy samples contained foci of myocyte necrosis and were labeled Rejectors. The two samples immediately preceding Rejector biopsies were labeled Predictors (n = 44). All remaining samples were labeled Others (n = 78). Endocardial and interstitial infiltrates, interstitial mononuclear cells, pyroninophilic mononuclear cells, polymorphonuclear leukocytes and other cells (eosinophils and plasma cells) were significantly increased in graded severity in Rejector biopsy samples as compared with Predictors or Others (p less than 0.001, ANOVA testing). These variables cannot distinguish Predictor biopsy specimens from Others. On the other hand, interstitial edema, perivascular karyorrhexis and perivascular infiltrate with intermyocyte extension are histologic abnormalities that can distinguish Predictor biopsy samples from Others (p less than 0.001, ANOVA testing). Multiple logistic regression analysis indicates that the relative risk of developing myocyte necrosis when a biopsy sample contains interstitial edema is 8.1. With perivascular infiltrate with intermyocyte extension in addition, the relative risk is 41.4. In summary, three histologic abnormalities have been identified that help predict the future development of myocyte necrosis within the next two endomyocardial biopsies. Biopsy specimens with these abnormalities probably represent early cardiac rejection before the development of myocyte necrosis.


Subject(s)
Graft Rejection , Heart Transplantation , Myocardium/pathology , Biopsy , Erythrocytes/pathology , Humans , Monocytes/pathology , Necrosis/pathology , Neutrophils/pathology , Probability , Retrospective Studies
6.
J Am Coll Cardiol ; 4(6): 1123-34, 1984 Dec.
Article in English | MEDLINE | ID: mdl-6334108

ABSTRACT

To ascertain the immediate effects of coronary artery bypass grafting on regional myocardial function, intraoperative transesophageal two-dimensional echocardiograms were obtained in 20 patients using a 3.5 MHz phased array transducer at the tip of a flexible gastroscope. Cross-sectional images of the left ventricle were obtained at multiple levels before skin incision and were repeated serially before and immediately after cardiopulmonary bypass. Using a computer-aided contouring system, percent systolic wall thickening was determined for eight anatomic segments in each patient at similar loading conditions (four each at mitral and papillary muscle levels). Of the 152 segments analyzed, systolic wall thickening improved from a prerevascularization mean value (+/- SEM) of 42.7 +/- 2.9% to a postrevascularization mean value of 51.6 +/- 2.6% (p less than 0.001). Thickening improved most in those segments with the worst preoperative function (p less than 0.001). Chest wall echocardiograms obtained 8.4 +/- 2.3 days after operation showed no deterioration or further improvement in segmental motion compared with transesophageal echocardiograms obtained after revascularization. Thus: regional myocardial function frequently improves immediately after bypass grafting, with increases in regional thickening being most marked in those segments demonstrating the most severe preoperative dysfunction, and this improvement appears to be sustained; and in some patients, chronic subclinical ischemic dysfunction is present which can be improved by revascularization.


Subject(s)
Coronary Artery Bypass , Coronary Disease/surgery , Echocardiography/methods , Aged , Computers , Coronary Disease/physiopathology , Female , Hemodynamics , Humans , Intraoperative Care , Male , Middle Aged , Myocardial Contraction , Postoperative Period , Time Factors
7.
Am J Psychiatry ; 142(8): 950-3, 1985 Aug.
Article in English | MEDLINE | ID: mdl-4025592

ABSTRACT

The authors implemented a new procedure for analyzing phencyclidine (PCP) content in hair. They compare the results of analyses of hair with results of analyses of blood and urine in 47 patients newly hospitalized with acute psychiatric illness. Hair analysis identified 11 patients who had used PCP, and blood and urine analyses did not identify any among the sample population. In three patients, the results of hair analysis aided in establishing a diagnosis of PCP intoxication. The authors discuss interpretations of their findings and psychiatric applications of this new technique.


Subject(s)
Hair/analysis , Hospitalization , Mental Disorders/complications , Phencyclidine Abuse/diagnosis , Phencyclidine/analysis , Adult , Female , Humans , Male , Phencyclidine/metabolism , Phencyclidine/poisoning , Phencyclidine Abuse/complications , Phencyclidine Abuse/metabolism , Radioimmunoassay/methods
8.
Am J Clin Nutr ; 31(3): 457-65, 1978 Mar.
Article in English | MEDLINE | ID: mdl-629217

ABSTRACT

The effect of Ehrlich ascites tumor growth on selenium-turnover rates and selenium-75 distribution in liver, kidney, and immunological tissues (spleen, thymus, and lymph nodes) was investigated in Swiss Webster mice that had been prelabeled with selenium-75. Ehrlich ascites tumor caused a decrease in the selenium-75 content of liver, kidney, and thymus; it also decreased the rate of the total-body selenium-turnover. In liver, depletion of selenium-75 was almost as great as that produced by a selenium and vitamin E-deficient diet. When mice had been fed an antioxidant-deficient diet, considerable quantities of selenium-75 were accumulated by the tumor; the specific activity of the tumor increased 9-fold over that in antioxidant-supplemented mice. The same diet produced a premature, and in some cases drastic, contraction in tumor volume. The possible significance of tumor-induced antioxidant deficiencies to the etiology of certain paraneoplastic syndromes is discussed.


Subject(s)
Carcinoma, Ehrlich Tumor/metabolism , Selenium/metabolism , Vitamin E Deficiency/metabolism , Animals , Antioxidants , Cryptococcus , Kidney/metabolism , Liver/metabolism , Mice , Organ Size , Selenium/deficiency , Spleen/metabolism
9.
Mech Ageing Dev ; 12(3): 261-8, 1980 Mar.
Article in English | MEDLINE | ID: mdl-6259453

ABSTRACT

The effectiveness of a recently developed isotopic in vivo assay for the measurement of delayed-type hypersensitivity (DTH) was compared to that of the conventional skin sensitization assay based on the ear-swelling index. DTH was measured in young and old C57BL/6 mice under conditions of normal health, spontaneous reticular cell sarcoma, Sendai virus infections and under the above conditions, while being treated with a potential immunorestorative agent, mercaptoethanol. A good correlation was observed between the two types of assay. However the reliability and sensitivity of the isotopic assay was found to be superior to the conventional skin sensitization assay. Thus, under optimum conditions, the swelling assay showed a 35% decline in DTH in old mice, and the isotopic assay a 62% decline.


Subject(s)
Aging , Hypersensitivity, Delayed , Animals , Dinitrofluorobenzene/immunology , Lymphoma, Large B-Cell, Diffuse/immunology , Mercaptoethanol/pharmacology , Mice , Mice, Inbred C57BL , Parainfluenza Virus 1, Human/immunology , Paramyxoviridae Infections/immunology , Skin Tests
10.
Mech Ageing Dev ; 8(5): 311-28, 1978 Nov.
Article in English | MEDLINE | ID: mdl-215851

ABSTRACT

Three different vitamin E effects, suggestive of specific antioxidant effects, were discovered in the protective action of vitamin E against respiratory decline (a decrease in mitochondrial respiration attributed to a "leakage" of electron transport radicals). No correlation was found between respiraotry decline and random lipid peroxidation. The mechanisms behind two of the three atypical vitamin E effects were defined. Both involve an artifact in the TBA assay for lipid peroxidation. This artifact occurs when TBA assays are carried out in the presence of sucrose and acetaldehyde; the latter is produced from ethanol, the solvent used to add vitamin E to preparations. The artifact in the TBA assay for peroxidations appears also to be responsible for differing interpretations of the hepatotoxic effect of ethanol.


Subject(s)
Mitochondria, Liver/metabolism , Oxygen Consumption/drug effects , Vitamin E/pharmacology , Acetaldehyde/metabolism , Animals , Cell Fractionation , Cytosol , Ethanol/pharmacology , Lipid Metabolism , Male , Microsomes, Liver , Mitochondrial Swelling/drug effects , NAD/pharmacology , Rats , Thiobarbiturates/metabolism
11.
Am J Surg Pathol ; 18(4): 338-46, 1994 Apr.
Article in English | MEDLINE | ID: mdl-8141428

ABSTRACT

Accelerated arteriosclerosis is now the major long-term complication of heart transplantation. Defining the risk factors associated with the development of accelerated arteriosclerosis will provide not only a means of identifying patients at risk for this complication but also clues to the etiology of accelerated arteriosclerosis. The purpose of this study was to examine the relationship between peritransplant myocardial ischemic injury and the development of accelerated arteriosclerosis. In a case-control study we examined the first three endomyocardial biopsies from 50 heart transplant recipients and graded the degree of ischemic injury present in these biopsies. The histologic changes graded in the biopsies included contraction band necrosis, coagulative necrosis, and macrophagic removal of ischemically injured myocytes. Of the 50 recipients included in the study, 25 had angiographic evidence of accelerated arteriosclerosis and 25 did not. In multivariate analysis, which included the number of class I major histocompatibility (MHC) antigen mismatches between the donor and the recipient, the recipient's post-transplant cytomegalovirus status, the donor's age, and the number of rejection episodes, the histologic degree of ischemic injury present in the biopsies emerged as the strongest predictor of the development of accelerated arteriosclerosis (RR 2.6, 95% CI 1.2-5.8, p = 0.02). These results suggest that ischemic injury to the heart during the peritransplant period significantly contributes to the development of accelerated arteriosclerosis in heart transplant recipients and that histologic changes in early posttransplant biopsies can be used to identify recipients at risk of developing accelerated arteriosclerosis.


Subject(s)
Coronary Artery Disease/pathology , Heart Transplantation/pathology , Intraoperative Complications/pathology , Myocardium/pathology , Postoperative Complications/pathology , Adolescent , Adult , Biopsy , Case-Control Studies , Coronary Artery Disease/etiology , Cytomegalovirus Infections/complications , Female , Graft Rejection , Heart Transplantation/adverse effects , Heart Transplantation/immunology , Histocompatibility , Humans , Male , Middle Aged , Multivariate Analysis , Myocardial Ischemia/etiology , Myocardial Ischemia/pathology , Necrosis
12.
Transplantation ; 49(1): 20-5, 1990 Jan.
Article in English | MEDLINE | ID: mdl-2301013

ABSTRACT

Combination CsA with corticosteroids is the most commonly used maintenance immunosuppressive regimen after cardiac transplantation, although their high-toxicity profiles frequently limit their clinical benefit. Immunosuppressive agents that would act synergistically with CsA but without the toxicity profile of corticosteroids would be clinically useful. Thalidomide was removed from the market due to its teratogenic effects, although it has known immunomodulatory activity. The purpose of this study was (1) to determine whether maintenance immunosuppression with thalidomide and subtherapeutic doses of CsA can help prevent rat cardiac allograft rejection; and (2) to compare its synergism with CsA to the commonly used corticosteroid, methylprednisolone. ACI-LEW allografts were all treated with subtherapeutic doses of CsA (10 mg/g/day, s.c.) for 4 days. When CsA was then discontinued, severe rejection developed by posttransplant day 14. Group 1 received CsA alone. Group 2 received in addition oral thalidomide 100 mg/day for 14 days. Groups 3, 4, and 5 received CsA and methylprednisolone (low dose: 0.2 mg/kg/day s.c.; moderate dose: 2.0 mg/kg/day s.c.; and high dose: 20 mg/kg/day s.c. Twelve histologic parameters of rejection were semiquantitatively graded 0-4, and total pathology scores were determined. The combination of thalidomide and subtherapeutic CsA significantly reduced the severity of myocardial necrosis, interstitial inflammation, interstitial edema, and the total pathology score. Thalidomide was found to be equally as effective as low-, moderate-, and high-dose methylprednisolone. The results of this study suggest the potential clinical role of CsA and thalidomide in maintenance immunosuppressive regimens, thereby avoiding the use of corticosteroids.


Subject(s)
Cyclosporins/administration & dosage , Graft Rejection/drug effects , Heart Transplantation , Methylprednisolone/administration & dosage , Thalidomide/administration & dosage , Animals , Drug Therapy, Combination , Immunosuppression Therapy , Male , Rats , Rats, Inbred Lew , Transplantation, Homologous
13.
Transplantation ; 57(6): 900-6, 1994 Mar 27.
Article in English | MEDLINE | ID: mdl-8154039

ABSTRACT

Hyperacute rejection results in rapid destruction of a discordant cardiac xenograft and is characterized by antibody deposition, complement activation, and platelet aggregation. The importance of neutrophils is unclear. Complement inhibition prolongs discordant cardiac xenograft survival. The purpose of this experiment was to determine the relative roles of complement and neutrophils. Selective inhibition of complement and neutrophil adhesion was used in a guinea pig-to-Lewis rat cardiac heterotopic xenotransplant model. NPC 15669 (N-[9H-(2,7-dimethylfluorenyl-9-methoxy)carbonyl]-L-leucine), a member of a new class of antiinflammatory agents termed leumedins, specifically prevents recruitment of neutrophils at inflammatory foci by inhibiting upregulation of the CD11b/CD18 adhesion molecule. Soluble complement receptor type 1 (sCR1, BRL 55730) is a potent inhibitor of the alternative and classical complement pathways. Group I (n = 13) received saline vehicle i.v. Group II (n = 15) was treated with NPC 15669 (10 mg/kg i.v. bolus) prior to reperfusion. Group III (n = 13) was treated with sCR1 (20 mg/kg i.v. bolus) prior to reperfusion. Group IV (n = 13) received both NPC 15669 and sCR1. Two xenografts were harvested at each interval time point (Groups I and II, 1, 2, 4, and 6 min; and Groups III and IV, 6, 15, 30, and 60 min). The remainder were followed to cessation of graft function. Graft survival was significantly increased in group IV and group III-375 +/- 13.4 min (mean +/- SD) and 112 +/- 29.4, respectively (P < .05), compared with 9.9 +/- 6.3 in group II and 8.7 +/- 4.9 in group I. Extreme interstitial hemorrhage and edema and contraction band injury were present in group I-III animals at end-stage, and neutrophil infiltration in group III. In group IV grafts, there was a decrease in these parameters despite the longer survival time, and at end-stage rejection the cellular infiltrate was primarily mononuclear. This study demonstrates that complement is an important mediator in early xenograft HYP injury. Combined treatment with NPC 15669 and sCR1 results in reduced histologic injury at all time points and longer graft survival than with sCR1 alone. These results suggest that neutrophil and complement activation play synergistic roles in the pathogenesis of xenograft hyperacute rejection. Neutrophil inhibition may prove to be an important component of multimodality therapy for hyperacute rejection, particularly in less-discordant transplants.


Subject(s)
Complement Inactivator Proteins/pharmacology , Heart Transplantation/immunology , Neutrophils/cytology , Transplantation, Heterologous/immunology , Animals , Anti-Inflammatory Agents, Non-Steroidal/pharmacology , Cell Adhesion , Graft Rejection/prevention & control , Graft Survival/drug effects , Guinea Pigs , Leucine/analogs & derivatives , Leucine/pharmacology , Rats , Rats, Inbred Lew , Receptors, Complement/physiology , Solubility
14.
Transplantation ; 46(1): 93-8, 1988 Jul.
Article in English | MEDLINE | ID: mdl-3134757

ABSTRACT

Autopsies from nine patients who had received a cardiac allograft transplant and one with a combined heart-lung transplant were assessed for histologic evidence of pseudo-graft-versus-host disease (pseudo-GVHD). Five of the ten patients had GVHD-like changes in two or more tissues, including prominent lymphocyte-associated bile duct injury consistent with marked hepatic pseudo-GVHD and mild cutaneous changes resembling GVHD. A sixth recipient had marked changes in the liver, but autopsy restrictions prevented examination of the skin. A seventh recipient had only mild pseudo-GVHD changes limited to the skin. In contrast, a series of six patients who were candidates for cardiac transplant had no specific pathologic changes suggesting pseudo-GVHD. The majority of those with pseudo-GVHD had received nonirradiated blood product transfusions, raising the possibility of posttransfusion engraftment and GVHD. Unlike the posttransfusion GVHD, however, two of the six developed GVHD-related complications late with a latent period of five and 9.5 months, and two recipients received no transfusions. All were receiving only modest doses of immunosuppressive agents at the time they developed liver function abnormalities, including low or tapering doses of cyclosporine (CsA). In some of these recipients, therefore, the pseudo-GVHD changes may well represent an autoimmune reaction resembling the post-CsA model of autoimmune disease.


Subject(s)
Autoimmune Diseases/etiology , Graft vs Host Disease/pathology , Heart Transplantation , Heart-Lung Transplantation , Lung Transplantation , Adult , Graft vs Host Disease/immunology , Humans , Liver Diseases/immunology , Liver Diseases/pathology , Skin Diseases/immunology , Skin Diseases/pathology
15.
Transplantation ; 45(2): 275-9, 1988 Feb.
Article in English | MEDLINE | ID: mdl-2894084

ABSTRACT

Uncontrolled pulmonary hypertension during autoperfusion of the heart and lungs for preservation has been described, and it may result in extensive pulmonary injury and occasional early failure of the preparation. In order to investigate the neurohumoral mediators of the vasoconstrictor response in the pulmonary circulation of the autoperfused working heart-lung preparation, heart-lung organ blocks were harvested from calves, placed in a normothermic autoperfusion circuit, and studied. Effects of beta-adrenergic stimulation with isoproterenol, nonspecific vasodilatation with nitroglycerin, alpha-adrenergic blockade with phentolamine, phospholipase A2 inhibition with methylprednisolone, cyclooxygenase inhibition with indomethacin, and white blood cell depletion were independently evaluated. Untreated animals, pre- and postexplant, served as controls. Multipoint pulmonary vascular pressure-cardiac output plots were constructed for each animal. An index of pulmonary vascular resistance was obtained from the linear relation: mean pulmonary artery pressure minus pulmonary capillary wedge pressure divided by cardiac output. An intense flow-dependent pulmonary vasoconstrictor response was confirmed to exist in the denervated bovine autoperfused working heart-lung preparation. Isoproterenol afforded better protection against this response than the other agents studied. White blood cell depletion reduced postexplant pulmonary vasoconstriction, implying that circulating polymorphonuclear leukocytes mediate the response in the autoperfused working heart-lung preparation. White blood cell depletion and the administration of selected pharmacologic agents provide modalities for regulating the pulmonary vasoconstrictor response, and thus may enhance lung preservation in the autoperfusion model.


Subject(s)
Heart Transplantation , Heart-Lung Transplantation , Lung Transplantation , Neurotransmitter Agents/physiology , Organ Preservation/methods , Perfusion/methods , Vasoconstriction , Animals , Blood Gas Analysis , Cattle , Heart/physiology , Indomethacin/pharmacology , Isoproterenol/pharmacology , Leukopenia/physiopathology , Lung/blood supply , Lung/physiology , Methylprednisolone/pharmacology , Nitroglycerin/pharmacology , Phentolamine/pharmacology , Pulmonary Wedge Pressure/drug effects , Transplantation, Autologous/methods , Vasoconstriction/drug effects
16.
Transplantation ; 56(3): 535-40, 1993 Sep.
Article in English | MEDLINE | ID: mdl-8212146

ABSTRACT

The development of post-transplantation coronary graft disease (CGD) is a major cause of late morbidity and mortality. Recent reports have suggested that CGD is a type of chronic vascular rejection, possibly enhanced by cofactors such as concurrent CMV infection and hyperlipidemia. It remains controversial whether established CGD can be improved by modifications in immunosuppressive therapy. The purpose of this study was to examine whether CsA could reverse or halt the progression of CGD after it was already established. Lewis to Fisher (F-344) heterotopic heart allografts develop CGD resembling human disease. Group 1 (n = 29) had no CsA therapy for chronic rat CMV (RCMV) infection in recipients for 8 weeks before transplant. Group 2 (n = 17) had chronic RCMV infection along with CsA therapy from days 15 to 28 post-transplant. Allografts were killed at 2 and 4 weeks and 90 days post-transplantation. In group 1, leukocyte adhesion to arterial endothelium and intimal hyperplasia were well established at 2 weeks and progressed to stenotic, proliferative arterial lesions at 4 weeks. In group 2, CsA therapy was effective in significantly reversing histologic parameters of vascular rejection such as leukocyte adhesion, intimal proliferation, and periarterial edema at 4 weeks. By 90 days, however, arterial pathology was as severe as in group 1. In conclusion, these results support the hypothesis that CGD is a form of chronic vascular rejection, and once established, can be significantly modified by CsA therapy. These effects are not permanent, and progressive CGD recurs after CsA therapy is discontinued.


Subject(s)
Arteriosclerosis/prevention & control , Cyclosporine/therapeutic use , Animals , Arteriosclerosis/etiology , Arteriosclerosis/microbiology , Cytomegalovirus Infections/complications , Graft Rejection , Heart Transplantation/adverse effects , Rats , Rats, Inbred F344 , Rats, Inbred Lew , Time Factors , Transplantation, Homologous/immunology
17.
Transplantation ; 46(3): 346-51, 1988 Sep.
Article in English | MEDLINE | ID: mdl-3047923

ABSTRACT

Eight beagles receiving heterotopic (cervical) cardiac allografts from outbred donors were evaluated by serial 31P NMR, septal endocardial biopsy, and left ventricular pressure measurements for signs of rejection. Early postoperative myocardial energy levels, as assessed by ratios of phosphocreatine to inorganic phosphate (PCr/Pi) and phosphocreatine to beta-ATP (PCr/B-ATP), were acceptable in all recipients. In these nonimmunosuppressed animals, the mean ratios of PCr/Pi and PCr/B-ATP progressively decreased, with a greater than 25% reduction noted by postoperative day two and greater than 50% reduction by day three. In sharp contrast, left ventricular end-diastolic pressures remained stable and at baseline levels for the first three postoperative days, and only then markedly increased. Likewise, histologic evidence of rejection did not become prominent until postoperative day four. These results suggest that metabolic abnormalities significantly precede either functional or histologic changes in rejecting allografts. The early detection of these metabolic changes by 31P NMR appears to have important potential for the noninvasive diagnosis of cardiac allograft rejection.


Subject(s)
Graft Rejection , Heart Diseases/metabolism , Heart Transplantation , Animals , Blood Pressure , Dogs , Energy Metabolism , Heart Diseases/pathology , Magnetic Resonance Spectroscopy , Phosphates/metabolism , Phosphocreatine/metabolism , Time Factors
18.
Transplantation ; 53(5): 1082-8, 1992 May.
Article in English | MEDLINE | ID: mdl-1585472

ABSTRACT

Neurological side effects associated with cyclosporine immunosuppressive therapy are generally believed to occur with CsA blood concentrations above the therapeutic range. The effects of high blood CsA levels on cerebral hemodynamics, metabolism, and electrophysiologic activity were studied in acute (no CsA prior treatment) and chronic (with CsA prior treatment) dogs. In acute animals, when parenteral CsA (10 mg/kg or 25 mg/kg) was administered intravenously (CsA blood level 2000-22,000 ng/ml), slight but significant time-dependent decreases in cerebral blood flow (CBF), prolongation of absolute latencies of somatosensory-evoked potential (SSEP), and brainstem auditory-evoked responses (BAER) were noted. In the CsA chronically administered animals (oral CsA 25 mg/kg/24 hr for 14 days, CsA blood level 1077 ng/ml), baseline cerebral physiologic parameters were normal, and the cerebral responses to further administration of CsA (25 mg/kg, CSA blood level 56,000 ng/ml) intravenously were similar to those of the acute animals. Animals given Cremophor EL, the solvent for parenteral CsA preparation, showed similar cerebral responses to those observed in animals given CsA. Thus this study showed that CsA, regardless of the dose given, whether chronically or acutely administered, or the solvent for CsA all induced similar cerebral physiologic responses. We suggest that the cerebral physiologic and functional changes associated with parenteral CsA administration were small and were likely caused by its solvent, Cremophor EL, rather than CsA itself. Furthermore on the basis of our results, it is unlikely that high blood CsA per se can account for neurological side effects that occur in immunosuppressed patients.


Subject(s)
Brain/metabolism , Cerebrovascular Circulation/drug effects , Cyclosporine/pharmacology , Animals , Cyclosporine/blood , Cyclosporine/cerebrospinal fluid , Dogs , Evoked Potentials, Auditory, Brain Stem/drug effects , Evoked Potentials, Somatosensory/drug effects , Female , Male , Oxygen Consumption/drug effects , Regional Blood Flow/drug effects
19.
Transplantation ; 61(2): 279-84, 1996 Jan 27.
Article in English | MEDLINE | ID: mdl-8600637

ABSTRACT

The cellular response to a wide variety of stresses results in the synthesis of a family of proteins termed heat shock proteins (HSPs). To determine if acute allograft rejection could induce these proteins in a transplanted graft, we examined the HSP response to acute cardiac allograft rejection and analyzed the effect of immunosuppression upon this response. Donor hearts obtained from either Lewis (LEW) or ACI rats were heterotopically transplanted in recipient LEW rats. There were 4 experimental groups: untreated isografted (LEW to LEW) animals (n = 14), untreated allografted (ACI to LEW) animals (n = 14), cyclosporine-treated (10 mg/kg SQ/day) isografted animals (n = 12), and cyclosporine-treated allografted animals (n = 12). Animals were sacrificed on posttransplantation day 2, 4, or 6 (time of rejection for untreated allografts); n = 4-5 for each time point per group. At these times tissue obtained from the transplanted heart was examined histologically and analyzed for HSP72 by quantitative Northern and Western blots. The level of HSP72 in the untreated allografts progressively increased between 2, 4, and 6 days posttransplantation and was significantly greater than that of the untreated isografts at all time points. The HSP72 response in cyclosporine-treated allografts was significantly reduced at 4 and 6 days posttransplantation compared with the untreated allografts. In contrast, there was no difference in the HSP response in treated versus untreated isografts. Additionally, there was no difference in HSP levels in cyclosporine-treated isografts and allografts. These findings demonstrate that HSP expression in the transplanted heart correlates directly with the evolution of acute allograft rejection, and that immunosuppressive therapy inhibits the HSP response. These studies also raise the possibility of a functional role for HSPs in the allogeneic immune response.


Subject(s)
Cyclosporine/administration & dosage , Graft Rejection/metabolism , Heart Transplantation , Heat-Shock Proteins/biosynthesis , Immunosuppressive Agents/administration & dosage , Animals , Graft Rejection/prevention & control , Male , Rats , Rats, Inbred ACI , Rats, Inbred Lew , Transplantation, Homologous
20.
Transplantation ; 47(1): 123-7, 1989 Jan.
Article in English | MEDLINE | ID: mdl-2643221

ABSTRACT

Numerous techniques have been devised for the harvesting of individual organs during a multiorgan procurement operation. Cardiopulmonary bypass with profound hypothermia (PH) has been employed in successful harvesting of heart-lung, kidney, pancreas, and liver grafts. This report summarizes our experience using CPB-PH for the harvesting of multiple organs from 10 brain-dead donors during the period from July 1983 to January 1988. Organs harvested included 10 heart-lungs, 17 kidneys (3 kidneys were not harvested due to anatomy and elevated creatinine), 1 liver, and 1 pancreas. Mean ischemic time for the distantly procured heart-lung grafts was 281 +/- 10 min. Adequate pulmonary function, as assessed by arterial blood gases, was observed in each heart-lung recipient (mean PO2 was 119 +/- 46 mmHg, 164 +/- 47 mmHg, 130 +/- 30 mmHg, 114 +/- 26 mmHg at immediate post-CPB, 6 hr postop, 24 hr postop, and postextubation, respectively). Mean length of intubation was 34 +/- 8 hr. Mean creatinines of kidney recipients at days 2, 7, and current creatinine were 7.4 +/- 3.6 mg%, 3.6 +/- 2.4 mg%, and 1.6 +/- 0.66 mg%, respectively. Eight kidney recipients (47%) required dialysis, (2 patients required only a single dialysis). Ninety-four percent of the kidney transplant patients are alive, and 88% (15/17) have functioning kidneys. One liver and 1 pancreas were harvested during this time period. Preservation was satisfactory in both the pancreas (Johns Hopkins Hospital) and liver (Dr. Thomas Starzl, personal communication). The technique of CPB-PH has resulted in excellent function of heart-lung grafts. Follow-up of the transplanted kidneys, liver, and pancreas utilizing this technique shows equal or better function compared with standard techniques. This technique offers other advantages in addition to satisfactory multiorgan preservation. Placement of an unstable patient on CPB ensures adequate organ perfusion and allows for a gradual yet uniform cooling of all organ systems. Cooling to a core temperature of 10-15 degrees C requires 30 min, during which time preliminary intraabdominal and mediastinal dissection can be carried out. Following cessation of CPB and subsequent exsanguination, organs can be more easily dissected in a near-bloodless field. This technique does not preclude additional crystalloid organ flushing. Since multiorgan procurement occurs with virtually every donor, this technique may be the optimal method providing excellent preservation, ease of dissection, and better control of hemodynamics during the operation.


Subject(s)
Cardiopulmonary Bypass/methods , Hypothermia, Induced/methods , Organ Preservation/methods , Heart Transplantation , Humans , Kidney Transplantation , Liver Transplantation , Lung Transplantation , Pancreas Transplantation
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